William webster



(No Model.)

vv- WEBSTER, Jr.

PROCESS 0F PURIPYING SEWAGB BY ELEGTRIGITY.

No. 398.101.l Patented Feb. 19, 1889.

UNITED STATESv PATENT OFF1CE.

lWILLIAM WEBSTER, JR., OF LEE PARK, LEE, 4COUNTY OF KENT, ENGLAND.

PROCESS CE PURIFYlNc-s'EwAeE BY ELECTRICITY.

SPECIFICATION 'forming para' erraten raten-mo; eesnonuatea February 1e, Issa. y

Application tiled December 22, 1887. Serial No. 258,724. (No model.) Patented in England January 27, 1887, No. 1,333 in France December 9, 1887, No. 187,497; in Cape of Good Hope 'January 28, 1888, No. 486 in Natal February 2, 1888; in Victoria February 8, 1888, No. 5,615; in New South Wales 4February 10, 1888, No.4961 in South Australia February 10, 1888, No. 961; in Tasmania February 12, 1888, No. E40/10; in NewvZealand February 20, 1888, No. 2,817, and in India April 13./ 28, 1888,

n To all whom it may concern.'

Be it known that I, WILLIAM WEBSTER, Jr.,

a citizen of England, residing at Lee Park, i

y1,333; France, dated December 9, 1887, No.

187,497; Cape of Good Hope, dated January 28, 1888, No. 436,; Natal, dated February 2, 1888; Victoria, dated February 8, 1888, No. 5,615; New South Wales, dated February 10,

1888, No. l195; SoutlnAInItraliardatfnl?elirulA .p

ary 10, 18,88, No. 961; Tasmania, dated February 12, 1888, No. 54:0/ 10; New Zealand, dated February 20,1888, No. 2,817, and India, dated April 13/28, 1888, No. 16 (522,) 0f which the following is a specification.

My invention has for its object the treatment of sewage and other impure Water by' electrolytic action in such manner as both to precipitate the solid matter suspended therein and to oxidize or otherwise disinfect the albuminoids andother organic impurities held in suspension o'r solutiontherein.

The invention consists, mainly,.in subject ing the liquid while flowing through reservoirs or channels to the electrolytic action of positive and negative electrodes of` iron having very extended surfaces. Nascent ammonia will by this means be evolved at the negative electrode, producing an alkaline reaction which effects the precipitation of the solid suspended matter, while at the positive pole nascent oxygen and-chlorine are evolved, producing an acid reaction, whereby t-he organic impurities held in suspension or solution are readily' decomposed and purified. Theformation of chlorine at the positive electrodes is due to the presence of large quantities of chlorides, &c., in the sewage. If this action is therefore carried on long enough,the sewage will Ybe converted into a disinfectiug-liquor. At the negative' pole ammonia and alkalies are set free, and directly an alkaline reaction is shown in the sewagethe precipitation of 3' the solid matter takes place, together with part of the calcium and magnesium salts, dre. 5o

In using iron positive electrodes, chlorites, or chlorides of iron are formed at the posit-Ive pole, and are partly precipitated by the alkaline reaction at'thenegative electrode in the form of hydrated oxide, which 'carries down 55 with it the suspended organic matter.

The nascent chlorine produced as above A described Willhave much greater efciency than the chlorine'present in chloride of lime, an-d the nascent oxygen will also havevmuch 6o more effect on the organic matter in the form of albuminoids than the oxygen of the atmoshere-... W Should'the liquid treated be insufficiently i charged with chlorides, I in some cases add chlorides thereto in order to produce the req v uisite amount of nascent chlorine, andfor thispurpose at sea-ports 1 employ sea-Water. The electrical. current required is necessarily fluctuating in amount, according to the amount of sewage to -be treated at any one time. The electro-motive force would vary from ten volts upward. It may be found desirable to alternate the current by means of a suitablcswitch, so as to produce a uniform wear of both sots of electrodes.

It has heretofore been proposed to subject sewage and impure-water toelectrol'ytic action by means of electrodes lof non-oxidizable material; -but I have found that it is essen. 8o tially necessary for obtaining a practical result of any value that iron electrodes should beused according to my present invention.

To successfully treat sewage for its purification and precipitation, it is absolutely necessary that a metallic salt of an oxidizable y metal-such as iron -hy-pochlorite or perchloride or protochloride-should be formed at the positive pole ;-otherwis e it is impossible to remove the suspended matter. A ilocculent precipitate of hydrated oxide. of iron is by this means at once produced, which effectually carries down the suspended matter. By using iron for the negative electrodes, on the l other hand, instead of carbon, whichwould be the only other practically availablematedisadvantage, conduct the current much better, so as at once to allow the alkalies set free to act upon the sewage and the iron salts produced at the positive pole. The pores of the carbon electrodes would also become cloggedwith the iron oxide formed, and the nascent hydrogen given oit in the pores of the carbon attacks the oxide and reduces it tothe 1netalv lic state, resulting in a considerable waste of power.'

In some cases the positive and negative electrodes maybe separated by a porous partition, so that there is a body of sewage tlowing in contact only with the positive electrode, and being subjected to an oxidizing action, and a second body flowing in contact only with the negative electrode and consequently subjected to the precipitating action, the two bodies being afterward either united together or kept separate from each other.

The apparatus which I employ for the purposes of my invention may be variouslyeonstructed. V

In the accompanying drawings, Figure 1 is a plan of a tank or reservoir, showing the electrodes arranged therein. Fig. 2is a vertical longitudinal section through the same. Fig. 3 is a vertical cross-section through it. Fig. et is a detail sectional view showing how the negative electrodes may be fitted to place.

AAccording to one arrangement I construct a reservoir in which are arranged electrodes extending alternately from opposite sides transversely across the1 reservoir or tank, so as to form this into a long narrow zigzag passage in the same, as indicated diagrammatieal yin Figs. 1,2, and. 3 of the accompanying drawings, which show respectively a part planpart longitudinal section, and a cross-section of the reservoir.

The positive electrodes av a a are fixed to the one side of the. 'reservoir and extend to within a certain distance of the other side, while the negative electrodes b are xed to this side and extend to within a certain distance of the first-nam ed side,vall the electrodes being fixed either permanently or in a removable manner to the floor of the reservoir, thus forming a closed zigzag passage between them, into which the liquid to be treated enters at a", and in which it` gradually flows along to the opposite end, where it is discharged, the bottom of the entire zigzag pasof any suitable material, fixed in the bottoni,`

so that the electrodes can be withdrawn and replaced when required. The electrodes being connected by conductors g g', respectively, to the positive and negative poles of a dynamoelectric machine or other generator of electricity, the sewage or other impure water in passing in contact therewith will, as before stated, be acted upon by the nascent ammonia generated at the negative electrodes b and by the nascent oxygen and chlorine at the positive electrodes a, and,` the passage between these beingeomparatively narrow and of considerable length, it Vwill be evident' that by the time the liquid arrives at the dischargeopening all particles thereof will have been yeitectually brought in contact with both sets of electrodes and subjected to the above-described precipitating and purifying action.

If necessary, an outlet closed by a valve may be provided at the one end of each length of the zigzag passage, through which the ac cumulated solid deposit may be discharged from time to time.

Having thus described the nature of this in vention, and the best means I know for carrying the same into practical effect, I claim The process herein describedof purifyingI sewage and other impure water, which consists in passing the same in contact with electrically-excited positive and nega-tive electrodes of iron, wherebyv salts of iron are produced at the positive electrode, which, in reacting with the alkalies produced at the negative electrode, form a occulent precipitate of ferrous hydrated oxide, which, together with the gases generated, eiect the precipitation of the solid matter and the purification of the impurities held in solution.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 2d day of Deeember, A. D. 1887.

` f 1WILLIAM WEBSTER, JR..

Witnesses: I

CHAs. D. ABEL,

Patent AA ent. JNO. P. M. ILLARD, Clerk to Messrs. Abel d2: Imray, Consulting Engineers dc Patent Agents, 2S Southampton Buildings, London, 'I/V. C'. 

